Description: Prostate adenocarcinoma (PCa) is the most prevalent noncutaneous cancer in American men and the second leading cause of cancer deaths. When detected early, survival rates may be enhanced by radical prostectamy or external beam radiotherapy; consequently, reliable tests for early detection are of paramount importance. Monoclonal antibodies (MAb) are used to detect elevated levels of prostate specific antigen (PSA) in serum, but the correlation with PCa is controversial. There is a need for an expanded collection of PCa-specific monoclonal antibodies. The investigator proposes to use recombinant antibody-phage-display technology to select MAbs that bind to localized and metastatic PCa tissue, but do not bind to normal tissue. They will molecularly clone antibody genes from PCa-binding hybridomas and use them the develop methods for selection of MAb-phage on PCa biopsy specimens. These methods will be used to isolate novel MAbs from libraries prepared from immunized mice. The MAbs derived from this study will be useful for basic research into the nature of the cancer, for clinical diagnostics, and for targeted treatment of prostate cancer.